Instrument link movement



Oct. 19, 1937. 1.. c. IRWIN INSTRUMENT LINK MOVEMENT Filed July 50, 1932 M M s R Y W MM W m M N M. WWW fl WITNESS Patented Oct. 19, 1937' T7QUN'ITED STATES PATENT OFFICE I s rrtUMEN'r' LINK MOVEMENT Lawrence C.-Irwin, Brooklyn, N.'Y., assignor to Charles J..Tagliabue Mfg. (30., Brooklyn, N. Y.,

a corporation of New York Application J uly30, 1932, Serial No. 626,834

6 Claims; (01. 74 5'z9) The present invention relates to animproved movement or gearing for instruments in which a 'system :sensitively responsive to minute variations of a conditionto be ,Qbserved, maintained or controlled is connected with a translating system driven by or through the motion of the sensitive. system. in response tovar iations o f the condition to be observed or controlled, as. for example instruments provided with a pointe 42 epen arm or similar element of temperature or pressure indicating or. recording instruments or -of indicatingpor. recording controllers, It is the object of .the invention to providea mechanism of -this type which is simple. in ,c nstruction and =easy pf. assembly, is ;c,apab e .Df, exerting the ry force p a the pointe 01', e iva t l m nt; requires nocom cated and l bo i us-=adjust n s a calibration/s e tabl she clearanceless constant-fric ion connection be; 5.2 -tween the,sensitive systemgand the translating system, automatically preservative of such connection .nQtWithStanding, wear. due to vibration :orrelativemotion.ofthe part and can be m anufactured:.on a large, scale withahigh degree of p.2 uniformity'andrat-a low; cost.

the-preferred embodi n o th pres t invention, I employ as, apart ofthe sensitive ..sys'tem.ja metallic bellows or of considerable crosslsectionaLarea; with which coasts-i t mpe e steel ,spiral spring, V-for transmittiug;;mQYQmQ .tozcaopointerdorpen arm o r other me'inber of an t -devichin r spons ip' HQFE P QP in temperature or pressure at a selected place -underimeasur ement, control or under both meas- Maurementiand QOILHZQL h resultant inp me of. the. mechanism depends almost entirely upon -the action0f the temperedsteel spring since the .metallic, bellow ha c par ively li tleresistance -;.Also,,due to the comparatively large crossmiQsectiomaL area of the bellows, the force exerted s; -the,reby. is co erab r% th same. i s .JdirQQ an .spositi y f tua o ce-tha a abeiex rfi d= ihebellows s s lr r a t loperatealsoa pilotyalve forming part of a eontrol1er.;mech anism. These T factors permit the :zlin sa s ,b twe the. .bq lq fi d; the Pointer --pen.i m ;tQ-b=; min su h. ii lle h re:qui i'e n oQsp e aLfitting. It is .howeye if'gfe's- .sential that -th nlgagebetween .th egsensitive ,w system) epresente 'b y the bellows and the translating lsystem representedjby the .pointer or other element affected by" the sensive system. shall'be. so contrived; and arranged '7 as to maintain; constant 'thel'relation between the s iss istiv srsie i a fiifihe tr nslating Ts'ystin v notway defining the scope thereof. ,fing, Fig. 1 is a plan View of an indicator movefm'ent embodying the present invention; Fig. 2' is an end'view thereof; and Fig. 3 shows a dewithstanding wear or the eifect of vibrations or relative movement of the parts due to other causes.

One of the important features of the invention resides in a novel connection between the 5 actuating bellows and spring and. the indicatingor recording parts which is capable of resisting the strains incident to the frequent oscillation thereof by the bellows and spring and is capable also of taking up wear automatically while maintaining the relationship of the parts constant, and thereby insuring accuracy of transmission of the impulses from the responsiv e mechanism to the indicating or recording parts.

'In the preferred form of the invention, this connection comprises a link arranged between ,a lever actuated by the bellows and spring and a lever or other movable device connected with or forming part of the indicating or recording element. The link is formed, at'least at its ends, of two spaced resilient members which are 'adapted to -be frictionally connected with the other parts under tension in such a way that wear on' the connection is absorbed by such resilient members. Thus, the pairs of resilient mem bers at the ends of the linlrmay be sprung over the associated parts which are to be conor projections, the parts being so dimensioned that in the assembled state the resilient members are under tension.

Other features and advantages of the invention will become evident. from the following de- 'scription, and the elements of novelty will be pointed out in the appended claims.

" Inthe accompanying drawing is illustrateda particular form of the invention Without in any 40 In said drawtail in perspective. 1 I

As shown in Figs. 1 and 2, a metallic bel-' lows l is securely fastened to a support or frame 2 by means of a nut 3 mounted upon a threaded hollow stem 4 projecting from the bottom of the bellows and passing through a suitableopning in the frame.

to the upper :portion of the bellows. This movement asplate 9 provided with'a'pointe'd projection Ill Jbearing upon'the'upperiac'e of the lever. The -right-hand end of leverr5 which'is the motiontransmitting member of the sensitive system and 'whichmoves'in response to Variations in thecondition tobe observed; recorded, or controlled, .is'

:providedwith an 'ear' 5a upon :which is pivoted alink ii whose upper .end ispivotally connected member l2 mounted; l4 journalled in thei with an arm lZa of .a rocker fol-Oscillation upon a shaft horizontally dispos d arms bracket secured wthe main, frameQIin any 7 i, suitable manner, "as by themotionfof the lever V 716 :jwhichgengages thechart I (see Fig; 2).

chart-is mounted upon aplate (not shown) which f 25 ,is rotated in known'manner by a clock meohapf 'the'rocker member '12 is the chart I 5 andhas attachedithereto a pen or stylus rnism" 15a:

V providedf with suitable depressions- 'orgapertures' c; 1;, He for receiving and holding the enidsfofthe'pin's 40 tion shown in Fig; 1 but'a'utomatic ally 5,

; 1f ortiqns and l lb b 7 i other: and therefore merely moving towardflthe 1 baserof the tapered p'ortions 5b and l2eas' l wear,

ptype illustrated, utilizing other Theilink'l l-is;v composed of two -;flexible plates r :Ha'and Hb held incspaced apart relationship by a block 'I le through which pass rivets lid,- B'oth :the ear: fiaj and arm'lgq are taperedor pointed at 7 both faees, or 'are provided with pro} ecting pins or studs, havingtapered 01" conical portiohsSb, lZc', thel iour projectionsj 5b; and; 1 2c all lying m;

an, approximately;commonfplane; so? as to avoid rrtorsion or twisting strainson thelink II when 'thefree ends jof the plates 11 leaf and, l lib are 7 sprung over suchfacesgor'jpins. The plates are 7 v3 s notonly: easy. of assembly,

*tiofi of -the instrume "moving parts; ispracticallY fian i h l la eing :biased toward: each foecas'ioned'b r 'ibration or'otherwiseioccurs at the r ploye d with mechanism {other than the specific t for example, in instruments kinds of actuating means such a Bourdon' sprin'glz V by' T i r l o e he r" IB Y be ad u t d 1 I V ,s'crew 3y"pmger dmtionfvoi the screw, the spring" Yni'ay be set to a definitepoint; indi- 'cjatedeby the punter?! 6; on the chart {5,1 eerie,- spending to, the temperature ofthe thermostatic 1 1, I lbulbtrltwhichris located atthec placejwhosetern perature '1 is fbeing measured orv recorded; f-Two' stops-in the formpfgadjustablescrews'l9iandl20 are f'mounted .upon the frame 2 and are .ad'j usted it limit the moyementof he pena rm lj tof the angebfitheiohart,

' erat ng the l pointer ofan vindicatingsinstrui'nfent with the aidgof ,a rack, andipiniom as thjorce" e certed by the bellows is 'v'er y 'lcons'iderable and suffices'for the. operation such;pointer.' s The mechanisms abeve described are charac- V stems terized by ektreme simplioity and easeof and reliable manner. As be 7 spring, {can bemanufacturedona large scaler f 7 lwitha high degree of uniformity, the'parts can be standardized and accurate instruments obtained:

screws-13a. 'Thear'mJZa'." 7 v V 7 with a minimum of calibration and adjustment;

7 element of the v translating system which is driven by or through; V

5 of thetsensitive system 'The" member 12 1s of sheet metal andisf re-r versely, bent at l2b'and has attached thereto, in

7 line with Lthe jshaft' fl 4 an 5 arm- TEL-shape which isfibe responsive. also 1. i r tzaroundctheedgeiof' the; r r V 1 V :4 It will be evidentpthat-my improvediindicator 'inovement'may be utilized with instruments other the specific example described hereinabovezmay V be resorted to] within the scope of the appended claims without departing from the spirit of'the "invention-2 3 l I" V '1 i f V" ;1.'-In instrument having j mechanism ssensitlve-wto H *changes in V a. physical condition and thus gen-Y :erally; subjected to almost constant movement, I a movable indicating, controlling,orrecording '1 member, and s a ;movable element-arranged 2.120

'When the parts: are assembled; .the plates; HQ and I lb bear: against the tapered pori pressure.- The .con'nec+* m j'bearing fmembersia takes ,cup'wear caused by yibra t 7 't because it is clearanceles's. The sensitivityofl the connectioniis preserved y r 7 reason of the'factfthat the friction between the pered: bearing inembergandjensfiginglsaidgmeina 'bers under suchjb ias said spring' plates beine free to m'ove under thegiinfluence fdt their-Lbias whereb iplagy is1eliminated?atl the };connecti0nS and the 'original relationship between the parts i andihence' ,theoriginal {calibration of th mm;

lco'nne ction; *corinectionlmayibeleinine tiiip er d-i' iv s ste sp nsiveitc I i t riat d 5 condition to be observedys'aidsystem including: p

' amember movablein response' to 'such variatioris,

atran slating systemincludingfl i f; iextendingitapered projections on the said membertofjthesensitiv syste ,Ya'pai or ppdsite'l c x nd n ",ta e ed biect V kq'r-m mbeic i h f tion'sjall lying-1 a i t f d n F 'sl u l i e n ed orropf ,turedblade portionsfeng agi J' t ns n the memb r bly, ca s it is'necessary only to' mount the several elements upon their pivots and to 'make a single adjustment of the spring'8, The construction or 1 lever H in the form of two spaced flexible plates '5 renders the connectionlthereof with the'lever 5 and with themember l2 (;1 igi;i1) avery simple i mattela; Theib'e11ows w capable of exerting a strong fo'rce and .can thu fl. f 10 operate, the train of linkagein a veryefiectivel h the bellows l and i5 It will belj understood that while I; have deso'ribed the bellows l asbeing'connected with a thermostatic bulb 18, such bellows can lbemade to the pressure at any: particular point by being directly connected to the pressure apparatus- V than-:that illustrated andQthat-variations from 5 r '5 'I c1aim: 7 i; a c r 7 indicati g, controlling or recording partake of the oscillating movement of said'sensi-i- 3 tivemechan'isin; .,a connection 'betweensaid eleertures at the spring 7 ends thereof; and tapered the ends of said'relement t r r r t bi p in dsf the 'plates'bein'g continuouslybiaseif towardi'th ta to take up wear at said tapered' bearingmembers "elem'enftfd itien pxImateIy con l'mon;

la an ia nkih vi Qa pair'of'iaperturedblade ru isengtgm hell t r8d-projectionslgn th driveni iriihbe Q't anslat egs te 4 central; connection betwee envie 3. In a precision instrument, a member movable in response to variations, a driven member, a link member and pairs of bearing assemblies operatively connecting said members, each pair of bearing assemblies having a male element consisting of a reduced diameter end portion and an adjacent tapered portion, and a female element having an aperture slightly larger than said reduced portion, and said link including means for biasing each of said apertures against the tapered portion of its mating element.

4. In a precision instrument, a driving member oscillatable about an axis, a driven member oscillatable about an axis parallel to said first mentioned axis, a link, and bearing assemblies connecting each end of the link with said driving and driven members, each bearing assembly consisting of a pair of male tapered elements and a pair of apertured bearings cooperating with said tapered elements, and said link including'resilient means for axially biasing said apertured bearings toward said tapered elements.

5. In a precision instrument, the combination of a driving and a driven member, a link member pivotally connecting said members, and a pivotal connection between each of said driving and driven members and said link members, said pivotal connection including a stud attached to one member with its axis in the pivotal line of said connection and shaped to taper down from its member to a reduced-diameter substantially I cylindrical end portion, and a bearing upon the coacting other of said members and having an aperture only slightly larger than said reduced stud end portion, and said link member including 1 means for biasing said bearing against said tapered stud.

6.'In a precision instrument, the combination of a driving and a driven member, a link and a substantially symmetrical pivotal connection between said link and each of said members including an aperture with its axis in the pivotal line of the connection and a stud having a tapered portion, said link including a plate carrying said aperture and means for biasing said apertured plate against said tapered portion of said stud.

LAWRENCE C. IRWIN. 

